For all the Pfefferman family dysfunction that drives much of Amazon’s “Transparent” (now in its fourth season) it is Alexandra Billings’ turn as Davina — friend, confidant and mentor to Jeffrey Tambor’s Maura — that gives the show its grounding, both as audience surrogate and the most well-adjusted person of the bunch.

“When the show’s creator, Jill Soloway, cast me I said, ‘Look, I am tired of playing transgender people in the hospital. Or hookers. Or a hooker on my way to the hospital. I’m tired of playing all these victimized people. I just want to be me.’ This is the way I sound, this is the way I dress, this is the way I talk.” The one main difference? “Davina does dress a little more ethereal than me, very flowy things. I’m really a jeans and T-shirt kind of gal. I shop a lot at Target — I love the Tar-jay.”

Billings was in Chicago this month filming scenes for the indie comedy “Freelancers Anonymous” and is shooting another Amazon series, “Goliath,” opposite Billy Bob Thornton.

Not that there haven’t been awkward moments over the years. “Quite frankly it’s a matter of deciding which story to tell,” she said.

There was the casting director who fell asleep in the middle of her monologue. “I kept talking and eventually she popped her head back up and said, ‘Wonderful, wonderful! That was just great.’ ”

But it was another unusual audition experience that stands out.

My worst moment …

“I was auditioning for a show — I won’t mention the name of it — and this particular TV show was improvised. So I didn’t get any sides (a script). The show had been on the air for a while by then and it was a very, very, very successful show.

“So I arrive and sign in, and there are these little slips of paper that have on it the situation that you’re supposed to improvise. And the situation reads as follows: ‘You are a transgender woman and you find yourself in the men’s bathroom with the star of the show and comedy ensues.’

“I’m reading this and I’m furious and highly insulted, and I don’t know what to do.

“And I’m in a room filled with other transgender female actors but here’s what I noticed: I’m like, wait a minute — these are all men in drag. And a couple of just men in men’s clothes, presenting as male. And I thought, ‘OK, this is bad.’

“I was just going to leave. And I’ve never done that before. But as I’m getting ready to leave, I run into another actress, Candis Cayne, who is also transgender. I’ve known her for a long time. And when I showed her the slip of paper she said, ‘Oh, no.’ This scenario was so not funny, that a transgender female ends up in a men’s room — oh, and the reason that we’re in the men’s room is that the line to the women’s room was too long.

“So together, Candis and I decided that if we both leave, they’re not going to know why. And they’re also not going to know why this isn’t funny and why it shouldn’t be a scene on the show. Instead of doing the audition, we decided to go in when each of us got called in, we would tell them why this was hurtful, not funny and unkind. So we did! She went in first. And then it was my turn.

“And the star, quite frankly to be perfectly honest, could not have been nicer. Could not have been nicer. But the producers who were there, or whoever they were — all white cis-gender men — were not happy with me at all.

“I said, ‘Guys, here’s why this isn’t funny: Comedy comes from truth. And never in a million years would a transgender woman go into the men’s room if the women’s line is too long. That’s why we’re fighting for unisex restrooms, guys. This is actually an issue — this isn’t funny.’

“They looked at me like I was nuts. And I said, ‘Guys, I’m a transgender person. Most of the people out there in the waiting room are men in drag, so I’m actually speaking from a place of truth and you’re actually making us the butt of the joke.

“And one of the guys at the table turned to me, and this is the only thing he said: ‘I don’t think this is the show for you.’ And I said, ‘Dear, I don’t think this is a show for anybody.’ And I left.”

The takeaway …

“This is about power — white, male, heteronormative, cisgender power. And if you look at Hollywood, that’s who is in control. Especially trans people of color, we’re at the bottom of the rung. So I feel like it’s important say something — not combative, not argumentative. It’s not even about debate. All I was doing was explaining, from a place of kindness and understanding and compassion. Just giving information. Not teaching, not lecturing, just saying, ‘Guys, here’s the ramifications of some of these jokes.’

“Because let me say, I love insult comedy — I love Joan Rivers and Don Rickles. I think that stuff is hilarious! And I don’t take myself so seriously that I can’t make fun of myself. I totally get that we need to let loose once in awhile. But when we’re in the center of the kind of political and human shattering that’s going on, when there are LGBT youth who turn on their TV and see this? Then the message is hopelessness, not humor.

“I can actually give you 999 different hilarious situations that actually have happened to me that we could exaggerate for comic effect. I could give you comical situations that are really funny but aren’t harmful. I’m fine with that!

“But I can no longer be a party to us being the punchline. I can’t do it anymore. It sends a message of hopelessness. And that’s not funny.

“I called my manager and told him what happened and he was like, ‘Good for you!’ So I felt supported. I felt like, ‘OK, I’m not alone.’ Whether they laughed at me when I left or had a change of heart, that was inconsequential to the fact that I was supported by my wife and by the people who work with me. It allowed me to speak louder.”

In 2015, Actress Candis Cayne recounted her own experience at that audition in an interview with The Hollywood Reporter, naming the show in question: HBO’s “Curb Your Enthusiasm.” When contacted by THR, a representative for the cable network said “the part never appeared” on the show.